The unending debate on radiation
by Andrew Teller
Mark O’Donovan, the ENS NEWS Editor-in-Chief, sent me the following quotation from an eminent Oxford University physicist, Professor Allison Wade:
“Radiation is about a thousand times less hazardous than is suggested by current safety standards. For many this will come as a surprise… The case for a complete change in attitude towards radiation safety is unrelated to the effects of climate change. But the realisation that radiation and nuclear energy are much safer than is usually supposed is of extreme importance to the current discussion of alternatives to fossil fuels and their relative costs. I have no links with the nuclear industry I just want to see the truth out there. So many people have been under a misapprehension for so long.”
His idea was to find out whether I could exorcise some common fears and rectify common misunderstandings regarding this subject.
The bad news is that I’m probably going to disappoint him: I can’t. The good news is that I think I can explain why I – or anybody else for that matter – can’t. Dispelling misconceptions about subjects linked to wider agendas always proves to be overambitious. And this is indeed the case of radiation, which has since long ended up as a pawn on the chessboard of nuclear controversy. Having an objective, dispassionate discussion on the impact of nuclear radiation has probably always been an out-of-reach dream. To be fair, both those for and against nuclear energy have a vested interest the matter. Being for/against it will make you less/more receptive to suggestions that radiation is dangerous even in the smallest quantities. The two issues are irremediably entangled: any evolution in one’s thinking on one score has the potential to affect the other, which increases one’s resistance to new pieces of information. As if this was not bad enough, one’s critical skills get all too easily blunted when an argument is recognised as reinforcing one’s current position. I would like to provide two examples of this unfortunate tendency. Unsurprisingly, they will stem from anti-nuclear literature: being in favour of nuclear energy, my critical skills are better trained to spot the weaknesses in the reasoning of those who oppose it.
The first one comes from a 1976 book, still in the early days of the anti-nuclear movement (three years before the Three Mile Island accident!): Unacceptable Risk – The Nuclear Power Controversy, by McKinley C. Olson. In this book, the author reported on the work done by a Dr Edward E. Martell, who came up with a quite clever theory on the dangers posed by alpha radiation. Dr Martell concluded that smokers are particularly exposed to lung cancer because each time they light a cigarette they inhale alpha-emitting material. Alpha radiation can be stopped by the lightest obstacle (cigarette paper is an oft quoted example!). But when there is nothing to stop it, as would be the case in the lungs, it can wreak havoc in the surrounding cells. Why would cigarettes contain meaningful quantities of alpha-emitting material? According to Dr. Martell, this is because there are tiny hairs on the surface of tobacco leaves. These hairs have “sticky glandular heads on their tips that collect radioactive dust particles”. These dust particles come from the fertilizer used to treat the tobacco soil: the fertilizer has a large phosphate content which in turn contains “rich amounts of radium”. Dr Martell insisted that it was radioactivity that was the culprit: he commented that only asbestos workers who were also smokers had a high lung cancer rate and that non-smoking asbestos workers were no more prone to lung cancer than other non-smokers. The outcome of his investigation was that the danger posed by radioactivity had been seriously underestimated and that admissible doses resulting from nuclear activities had to be drastically reduced.
We cannot blame Dr Martell and McKinley C. Olson for not having known that asbestos does not need the assistance of smoking to cause cancers. But we can wonder why they overlooked another basic flaw in this theory: if this interpretation was correct, the mechanisms described should provoke cancer with near certainty. How is it then that so many smokers escape the illness? Today the cause of lung cancer in smokers is ascribed to the thousand or so toxic chemicals found in cigarettes. Has this change in the understanding of the causation of lung cancer lead to a reappraisal of the impact of radiation? Not for those who oppose nuclear energy. And this is where the second example comes in.
In 2003, a so-called European Committee on Radiation Risk (it’s got nothing to do with any EU institution) issued recommendations that contradicted the official position of the International Committee on Radiation Protection (ICRP). In the present case, the reasoning does not rest any more on the basics of radiation protection such as the bodily damage induced per radiation type and the duration of residence of radioactive material in various organs. The problem is stated in terms of DNA damage, cell replication and repair, etc. Nothing wrong again with this, but two other factors are worrying for the non-specialist trying to gauge the validity of the report. First, it is not a piece of pure scientific investigation. The document starts with a sizeable exposition of the authors’ political and ethical views. Without even dwelling on the fact that I for one find their views repulsive, I submit that starting a research paper by indicating one’s personal political and ethical objectives is not the best way to convince the reader of its scientific worth. The reality of findings must be supported by critical observations, not by moral preferences. Second, when confronted with discrepant information, the elements that are dismissed are systematically those that do not agree with the authors’ broader objectives: it is impossible to believe that this way of sorting the facts out could be justified in each instance. So through a totally different approach, the same outcome is achieved: radiation protection recommendations leading to permissible levels of radiation much lower than those quoted by the ICRP. The very opposite of what Professor Wade is advocating. Those who are convinced that the impact of low level radiation is vastly underestimated are holding on.
Such lasting opposition is facilitated by the fact that many pieces of information, some of which are contradictory, have to be reconciled. Depending on the weighting coefficients allocated to each of them, one conclusion or the opposite one will be reached. Declarations such as Professor Wade’s are most useful in tilting the scale in a scientific direction, but this will not convince those who do not like the consequences entailed.